Basic parts of a circuit breaker
A circuit breaker is an electrical device that is designed to interrupt an electrical circuit when the current exceeds a certain level, known as the trip point. The basic parts of a circuit breaker include:
- Main Contact: These are the moving contacts that make and break the electrical circuit. They are typically made of a conductive material such as copper or silver.
- Trip Unit: This is the component that detects when the current exceeds the trip point and sends a signal to the main contact to open. The trip unit is usually a thermal or magnetic device.
- Thermal Element: This is a component that detects overheating in the circuit and sends a signal to the trip unit to trip the breaker. Thermal elements are often used in combination with magnetic elements.
- Magnetic Element: This is a component that detects excessive current flow in the circuit and sends a signal to the trip unit to trip the breaker. Magnetic elements are often used in combination with thermal elements.
- Arc Chute: This is a component that helps to extinguish the arc that forms when the main contact opens. The arc chute is usually a metal plate or a series of metal plates that are designed to dissipate the energy of the arc.
- Main Contact Spring: This is a spring that returns the main contact to its closed position after the breaker has tripped.
- Trip Coil: This is a coil of wire that is connected to the trip unit and provides the magnetic field that is needed to trip the breaker.
- Operating Handle: This is the part of the circuit breaker that is used to manually trip the breaker or reset it after it has tripped.
- Mounting Bracket: This is the part of the circuit breaker that is used to mount it to a panel or enclosure.
- Terminal Blocks: These are the parts of the circuit breaker that are used to connect the wires to the breaker.
These are the basic parts of a circuit breaker, although the specific design and components may vary depending on the type and manufacturer of the breaker.